Compressor thermal valve unit to route lubricant used in a compressor

ABSTRACT

A thermal valve unit is provided for use with an oil filled screw compressor. The thermal valve unit can be affixed to an exterior pipe segment and can include a thermally responsive element in thermal communication with compressed air traversing through the pipe segment. The valve unit can include a movable valve member actuated by the thermally responsive element that opens and closes oil passages to selectively route oil either to a heat exchanger prior to being delivered to the oil filled compressor, or directly to the compressor without passing through the heat exchanger.

TECHNICAL FIELD

The present invention generally relates to compressor based thermalvalve units, and more particularly, but not exclusively, to thermalvalve units that control passage of a fluid based upon the sensedtemperature of another fluid.

BACKGROUND

Providing compression systems that utilize lubricant in a compressionprocess with lubricant at an appropriate temperature remains an area ofinterest. Some existing systems have various shortcomings relative tocertain applications. Accordingly, there remains a need for furthercontributions in this area of technology.

SUMMARY

One embodiment of the present invention is a unique thermal valve unit.Other embodiments include apparatuses, systems, devices, hardware,methods, and combinations for actuating passages for the conveyance ofone fluid based on a temperature of another fluid. Further embodiments,forms, features, aspects, benefits, and advantages of the presentapplication shall become apparent from the description and figuresprovided herewith.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 depicts an embodiment of a prior art thermal valve unit.

FIG. 2 depicts an embodiment of a prior art thermal valve unit.

FIG. 3 depicts an embodiment of a thermal valve unit.

FIG. 4 depicts an embodiment of a thermal valve unit upon a pipe.

FIG. 5 depicts an embodiment of a thermal valve unit.

FIG. 6 depicts an embodiment of a thermal valve unit upon a pipe.

FIG. 7 depicts a schematic of a thermal valve unit in use with acompression system.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended. Any alterations and further modificationsin the described embodiments, and any further applications of theprinciples of the invention as described herein are contemplated aswould normally occur to one skilled in the art to which the inventionrelates.

With reference to FIGS. 1 and 2, a prior art thermal valve unit 50 isillustrated. The thermal valve unit 50 can be used with a compressionsystem (not illustrated) useful for providing a source of compressed airsuch as for a facility. In one nonlimiting embodiment the compressionsystem includes an oil filled screw compressor in which oil is used inconjunction with mechanical compressive elements of the screw compressorto assist in the compression process of air. It is desired in someinstances to thermally condition the oil such that it is neither toocool nor too hot when used with the mechanical compressive elements. Oilthat is too cool may condense water vapor from an air stream to becompressed leading to undesirable amounts of liquid water in the system.Oil that is too hot may degrade compressor performance.

The thermal valve unit 50 is configured to be fitted between respectiveends of neighboring compressor pipe, and includes a base 52 that isannular in nature and configured to fit between the ends of adjacentpipe. The circumferential extent of the annular shaped base includes afirst axial abutment side 54 that is opposite a second axial abutmentside 56, where the respective abutment sides 54 and 56 contact therespective ends of the neighboring adjacent pipe. The base includesapertures 58 which are configured to receive a fastening member, such asa bolt, fitted through corresponding apertures in a flange of compressorpipe.

The prior art thermal valve unit 50 also includes a thermally responsiveelement 60 that extends into a fluid flow stream of the pipes and whichis mechanically connected with a valve 62, and a housing that includes aseries of internal passages that can be selectively opened and closeddepending on a movement of the valve 62 which is actuated by atemperature response of the thermally responsive element. The fluidpassages leading to and away from the housing include oil from the sump(marked as reference arrow 68), oil to an oil cooler (marked asreference arrow 70), oil returning from the oil cooler (marked asreference numeral 66) and oil outbound to the compressor (marked asreference numeral 64). Depending on the valve position, oil can flowfrom 68 to 64, or can flow from 68, out through 70, returning from 66,and then to 64.

FIG. 2 depicts a cross sectional view of the embodiment illustrated inFIG. 1. The passages can be configured through action of the thermallyresponsive valve to route relatively warm oil returned from a sump of acompressor to an oil cooler for subsequent cooling in one mode ofoperation. In another mode of operation, oil that is returning from anoil sump can be routed to bypass the oil cooler and return directly tothe compressor for further use in the compression process. The valve 62includes apertures 72 which open to passage 66 when the thermallyresponsive element 60 urges the slidable valve element 62 to the rightas seen in the figure. The valve element 62 is hollow to allow oil topass from 68 directly to 64 via apertures 74 when the apertures 72 areclosed off by the surrounding valve body. The valve body is enlarged at76 to permit oil that proceeds from 68 to 70, then returns through 66 toflow through apertures 72 before exiting 64.

Turning now to FIGS. 3 and 4, one embodiment of the instant applicationincludes a thermal valve unit 78 mounted not between pipe segments as inthe embodiment above but rather upon a single pipe segment 80. Thethermal valve unit 78 is affixed on an exterior section of compressorconduit pipe and located at a position intermediate the ends 82 and 84of the compressor conduit pipe 80. In one form one or both of the ends82 an 84 can include flanges (FIG. 4 showing an embodiment in which bothends are flanged) which permit the piping to be attached to otherstructures, such as an inlet or outlet of a subsystem, to anothercompressor conduit pipe, etc. In one nonlimiting form the compressorconduit pipe can be attached at one end to an exit of a compressorhousing, and attached at the other end to a separator system.

The thermal valve unit 78 is used to regulate a temperature of oil usedin the oil filled compressor (not illustrated in FIG. 4, but a schematicof which is discussed below). In oil filled compressors it is desired touse oil that is of sufficient temperature to avoid condensation of watervapor contained in an air stream used for compression, but not hotenough to impact compression efficiency. Thus, it can be desired in somesituations to avoid use of an oil heat exchanger during those periods inwhich a temperature of the oil is low (such as, for example, duringstart up or low ambient temperature conditions), but to intentionallyuse oil that has traveled through an oil cooler/heat exchanger when thetemperature of the oil is warm enough to impact compression efficiency(such as, for example, after warm up and/or during hot ambientconditions).

The thermal valve unit 78 can include many of the same features as shownabove in FIG. 2. For example, the thermal valve unit 78 can include athermally responsive element 60 which projects into a flow stream ofcompressed air, a valve 62 located internal to a housing 86, apertures(such as 72 and 74) to that operate in conjunction with a valve body toselectively open and close internal passages, and openings 64, 66, 68,and 70 to permit oil to flow between components as discussed above. Thethermal valve unit 78 includes a base 88 which can be used to secure theunit 78 in place intermediate the housing 86 and the compressor pipe 88.

Though the thermally responsive element 60 in FIG. 3 is shown projectingaway from the base 88 of the thermal valve unit 78 and into a flowstream of compressed air within the compressor pipe 80, not allembodiments need be exposed to the flow stream. For example, in someembodiments an intermediate structure can be used to provide thermalcommunication between the fluid in the pipe 80 to the valve butotherwise shield the thermal valve unit 78 from contact with the fluid.For example, a thermally conductive material can be exposed to the fluidand otherwise provide thermal conductivity between the fluid and thethermally responsive element 60. Such a thermally conductive materialcould be exposed to the fluid in the pipe while the thermally responsiveelement 60 is located radially inside a periphery of the housing 86 ofthe thermal valve. Other arrangements are also contemplated.

The base 88 can take the form of a flange 90 as depicted in FIG. 3through which fastening devices (e.g. bolts) can pass to secure the base88 to the pipe 80. The base 88 can have any number of aperturestherethrough to permit insertion of fastening devices such as bolts tosecure the base to the pipe. In some additional and/or alternativeembodiments, the base can be chemically or metallurgically bonded to thepipe. Such metallurgical bonding can include a variety of techniquessuch as, but not limited to welding and brazing.

The base 88 includes an engagement surface (e.g. the underside of thebase 88 depicted in FIG. 3) that is generally arranged to be transverseto the axis of the thermal responsive element 60. In some forms theunderside of the base 88 can additionally and/or alternatively include arecess in the engagement surface into which can be placed a sealant suchas, but not limited to, an O-ring to provide a fluid tight seal for thepipe 80.

In some forms, as in the illustrated embodiment, the base 88 is acomponent having larger footprint that an intermediate neck 92 which islocated between the housing 86 and the base 88. The neck 92 in theillustrated embodiment includes a circular cross sectional shape, butcan take on different shapes in other embodiments. In some alternativeembodiments the base 88 can be the bottom side of the housing 86 suchthat the neck 92 is entirely absent.

The base 88 can be curved or flat depending on the needs in any givensituation, and in some forms can be shaped to interface with anembossment on the pipe 80. In those embodiments where the base 88 iscurved, the base 88 may extend only partially around the pipe 80 suchthat it can be directly affixed to the pipe 80 without being axiallyslid over an end of the pipe and into its fastening position.

The housing 86 depicted in the illustrated embodiment can be square incross section and substantially the same outer dimensions along thelength of the housing 86, but other shapes and sizes are alsocontemplated herein. For example, the housing 86 can be circular,conical, or any other geometric or non-geometric shape. As shown in theillustrated embodiment the housing 86 takes on a rectangular shape.

The housing 86 can be made from a variety of materials using a varietyof techniques. In one form the housing 86 can be made from a stampedsheet metal construction into which is located a valve body to providethe internal, or it can be cast into net or near-net shape, among manyother approaches and material types. In those embodiments in which avalve body is located within an external portion of the housing 86, suchan external portion can be referred to as a shell within which variousother passages and components of the thermal valve unit 78 reside. Theshell can have a constant thickness throughout the housing. In someforms the shell includes internal structures useful to structurallysupport the housing.

The housing 86 is structured to be located external to the pipe 80 andin some applications can be exposed to environment conditions withoutaid of a covering. In these applications the compressor unit may nothave an overall housing within which are located some or all of thecomponents of the compressor unit such as the motor, compressor, tubing,etc.

In some embodiments the housing 86 can have fittings installed tofacilitate connection to conduits/tubing/pipes/passages/etc. Thefittings can take on a variety of forms. In some embodiments the housing86 can include pre-formed holes through which a bolted connection can bemade to route oil to/from various components such as an oil sump, oilheat exchanger, etc.

The pipe 80 can be used for industrial purposes such as the generationof compressed air made through the compressor systems discussed above.The pipe 80 includes a through passage for the bulk conveyance ofcompressed air (and possibly mixture of compressed air and oil) asdiscussed above. The pipe 80 can also include an opening in its outercylindrical surface which permits exposure of the thermal valve unit 78to fluid traversing the pipe 80. Such an opening can be bordered by theembossment mentioned above, and is generally located in most embodimentsbetween the ends of the pipe. The opening in the pipe 80 can partiallyextend circumferentially around the outer part of the pipe 80.

The segment of pipe 80 can be any length (e.g. from a few inches to afew feet), and can be any configuration that includes straight pipesegments and curved pipe segments. In some forms the pipe 80 is formedas a coupler device that extends axially between two other large pipesegments.

As discussed above, the pipe 80 can include a mounting surface 94 uponwhich the thermal valve unit 78 will be coupled. The mounting surfacecan be curved or flat. The mounting surface 94 shown in FIG. 4 isdepicted as an embossment having a relatively flat surface shape, butother forms are also contemplated herein. For example, the mountingsurface 94 can take the form of a conventional exterior surface of apipe segment. In some forms the base may connect direct to the pipewithout an embossment in which case the base 88 may be a complementaryshape to the exterior of the pipe. The embossment on the pipe 80 can bemade from a variety of materials. In one form the embossment on the pipe80 is made from a material separate from the pipe 80 and is laterbonded.

Turning now to FIGS. 5 and 6, an alternative embodiment of the thermalvalve unit 78 is shown which includes pockets 96 are formed. Suchpockets 96 can be formed in the housing 96

Turning now to FIG. 7, an embodiment of the thermal valve unit 78affixed upon a pipe segment 80 can be integrated into a compressionsystem 100 having a variety of components (some of which were discussedabove). The compression system can include an oil filled screwcompressor 102 that receives air 104 to be compressed and delivered to acustomer. The compressor 102 provides a mixed stream of compressed airand oil to a separator 106 which provides for a compressed air output108 and a separated oil flow 110. The oil flow 110 is provided to a sump112 which collects the oil before routing the oil to the thermal valveunit 78. Based on a temperature of air traversing through the pipe 80,the thermal valve unit 78 can actuate to either route the oil from thesump 112 direct to a filter 114, or route the oil to a heat exchanger116 (such as an oil cooler) prior to delivering the oil to the filter114. The filter 114 can remove contaminate from the oil beforedelivering the oil for use in the compressor 102. The pipe segment 80 towhich the thermal valve unit 78 is affixed can represent a segmentlocated either downstream or upstream of the compressor 102.

One aspect of the present application provides an apparatus comprising acompressor thermal valve unit having: a thermal valve housing having anexterior shell that includes a plurality of apertures through which afluid can traverse, the housing enclosing an interior having a pluralityof passages in fluid communication with the plurality of apertures andthrough which fluid from the apertures can pass, a base disposed near anend of the thermal valve and structured to support the thermal valvewhen it is affixed to a compressed air system pipe, the base having athickness that extends from a bottom surface and a footprint defined inpart by a lateral length, the bottom surface of the base having a shapecomplementary to an external side surface of the pipe, wherein thethickness is shorter than the lateral length, and wherein the laterallength extends along an axial direction of the pipe, and a thermal valvehaving a valve body coupled to a thermally responsive element, the valvebody structured to move in response to excitation of the thermallyresponsive element to open and close one or more of the plurality ofpassages within the thermal valve housing.

A feature of the present application further includes a neck disposedbetween the thermal valve housing and the base, wherein the neckincludes a cross sectional area smaller than a cross sectional area ofthe thermal valve housing and smaller than a cross sectional area of thethermal valve base.

Another feature of the present application further includes wherein theexterior shell includes a plurality of opposing faces within which areformed the plurality of apertures.

Yet another feature of the present application further includes a pipeto which the thermal valve unit is affixed, the pipe having an inlet andan outlet and a side opening aperture that permits fluid flowing fromthe inlet to outlet to contact a portion of the thermal valve unit.

Still another feature of the present application further includes asealant disposed between the base and the external side surface.

Yet still another feature of the present application further includeswherein the external side surface includes an embossment upon which thebase is coupled, wherein the sealant is an O-ring, and wherein theO-ring disposed between the embossment and the base.

Yet another feature of the present application further includes thecompressor, an oil filter, and an oil heat exchanger.

Still yet another feature of the present application further includeswherein the thermal valve unit is a unitary stand-alone componentmanufactured separately from the pipe.

Another aspect of the present application includes an apparatuscomprising a compressor valve unit for use with a compressor and havinga housing within which is contained a plurality of reconfigurable fluidflow paths, a temperature responsive element disposed within thecompressor valve unit and coupled to a movable valve member, thetemperature responsive element configured to actuate the movable valvemember from a first position to a second position, the first positionconnecting a main inlet to a main outlet, the second position connectingthe main inlet to a heat exchanger outbound port and a heat exchangerinbound port to the main outlet, and a mounting base disposed at an endof the compressor valve unit for an external contact with a compressorpipe, the mounting base having a lateral periphery in thecircumferential and axial directions with dimensions sized to close offan accessory opening formed in an outer surface of the compressor pipe,the accessory opening oriented transverse to a bulk fluid flow path ofthe compressor pipe.

A feature of the present application further includes wherein themounting base includes a recess configured to receive a sealing member,wherein the pipe to which the mounting base is configured to mount isannular in nature, and wherein the mounting base forms a non-annularshape.

Another feature of the present application further includes wherein themounting base is planar and includes a groove into which can be fitted asealing member.

Still another feature of the present application further includeswherein the reconfigurable fluid flow paths are in fluid communicationwith the main inlet, the main outlet, the heat exchanger outbound port,and the heat exchanger inbound port, and wherein the housing includes aplurality of faces within which are located the main inlet, the mainoutlet, the heat exchanger outbound port, and the heat exchanger inboundport.

Yet another feature of the present application further includes whereinthe housing is quadrilateral in cross sectional shape such that the maininlet, main outlet, heat exchanger outbound port, and heat exchangerinbound port are dispersed around the housing, and wherein thecompressor valve unit further includes a neck between the housing andthe mounting base.

Still yet another feature of the present application further includes apipe having an internal passage structured to convey fluid betweenopposing openings on either end of the pipe, the pipe further includingthe accessory opening.

Yet still another feature of the present application further includeswherein the outer surface of the compressor pipe further includes anembossment to which is attached the compressor valve unit.

Still yet another feature of the present application further includeswherein the embossment includes a planar mounting surface, wherein themounting base includes a planar base surface, and wherein the planarbase surface is configured to mount direct to the planar mountingsurface of the embossment.

Still another feature of the present application further includes thecompressor, an oil filter, and an oil heat exchanger.

Yet another aspect of the present application includes a methodcomprising providing a pipe having a pipe segment defined by opposingpipe ends having respective openings through which fluid can pass, and alateral opening formed in the surface of the pipe which extends betweenthe opposing pipe ends, installing a thermal valve unit upon an exteriorof the pipe segment, the thermal valve unit having a temperatureresponsive member exposed to a fluid within an interior of the pipe, thetemperature responsive member capable of actuating a valve body upon achange in temperature, as a result of the contacting, covering thelateral opening formed in the surface of the pipe with a base of thethermal valve unit such that the thermal valve unit predominately restsexternal to the, and coupling a plurality of conduits to complementaryopenings formed in a housing of the thermal valve unit.

A feature of the present application further includes installing asealing device between the thermal valve unit and the lateral opening.

Another feature of the present application further includes wherein thesealing device is an O-ring, and wherein the coupling includes rotatinga threaded coupler to secure at least one of the plurality of conduitsto the thermal valve unit.

Still another feature of the present application further includeswherein the installing includes inserting the temperature responsivemember into an interior fluid passage space of the pipe, the interiorfluid passage space extending between the opposing pipe ends, and whichfurther includes affixing an embossment to the pipe segment, theembossment forming the lateral opening of the pipe.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiments have been shown and described and thatall changes and modifications that come within the spirit of theinventions are desired to be protected. It should be understood thatwhile the use of words such as preferable, preferably, preferred or morepreferred utilized in the description above indicate that the feature sodescribed may be more desirable, it nonetheless may not be necessary andembodiments lacking the same may be contemplated as within the scope ofthe invention, the scope being defined by the claims that follow. Inreading the claims, it is intended that when words such as “a,” “an,”“at least one,” or “at least one portion” are used there is no intentionto limit the claim to only one item unless specifically stated to thecontrary in the claim. When the language “at least a portion” and/or “aportion” is used the item can include a portion and/or the entire itemunless specifically stated to the contrary. Unless specified or limitedotherwise, the terms “mounted,” “connected,” “supported,” and “coupled”and variations thereof are used broadly and encompass both direct andindirect mountings, connections, supports, and couplings. Further,“connected” and “coupled” are not restricted to physical or mechanicalconnections or couplings.

What is claimed is:
 1. An apparatus comprising: a compressor thermalvalve unit having: a thermal valve housing having an exterior shell thatincludes a plurality of apertures through which a first fluid cantraverse, the housing enclosing an interior having a plurality ofpassages in fluid communication with the plurality of apertures andthrough which the first fluid from the apertures can pass; a basedisposed near an end of the thermal valve housing and structured tosupport the thermal valve when affixed to a compressed air system pipe,the base having a thickness that extends from a bottom surface and afootprint defined in part by a lateral length, the bottom surface of thebase having a shape complementary to an external side surface of thepipe, wherein the thickness is shorter than the lateral length, andwherein the lateral length extends along an axial direction of the pipe;and a thermal valve having a valve body coupled to a thermallyresponsive element, the thermally responsive element in thermal contactvia intermediate structure or directly exposed to compressed air whichtraverses the compressed air system pipe during operation, the thermallyresponsive element configured to directly assess temperature of thecompressed air, the valve body structured to move in response toexcitation of the thermally responsive element from a temperature of thecompressed air so as to open and close one or more of the plurality ofpassages within the thermal valve housing for the passage of the firstfluid.
 2. The apparatus of claim 1, which further includes a neckdisposed between the thermal valve housing and the base, wherein theneck includes a cross sectional area smaller than a cross sectional areaof the thermal valve housing and smaller than a cross sectional area ofthe thermal valve base.
 3. The apparatus of claim 2, wherein theexterior shell includes a plurality of opposing faces within which areformed the plurality of apertures.
 4. The apparatus of claim 1, whichfurther includes a pipe to which the thermal valve unit is affixed, thepipe having an inlet and an outlet and a side opening aperture thatpermits fluid flowing from the inlet to outlet to contact a portion ofthe thermal valve unit.
 5. The apparatus of claim 4, which furtherincludes a sealant disposed between the base and the external sidesurface.
 6. The apparatus of claim 5, wherein the external side surfaceincludes an embossment upon which the base is coupled, wherein thesealant is an O-ring, and wherein the O-ring disposed between theembossment and the base.
 7. The apparatus of claim 5, which furtherincludes the compressed air system pipe, a compressor structured toprovide the compressed air to traverse the compressed air system pipe,an oil filter, and an oil heat exchanger, and wherein the first fluid isoil.
 8. The apparatus of claim 7, wherein the thermal valve unit is aunitary stand-alone component manufactured separately from the pipe. 9.An apparatus comprising: a compressor valve unit for use with acompressor and having a housing within which is contained a plurality ofreconfigurable fluid flow paths structured to selectively flow a firstfluid; a temperature responsive element disposed within the compressorvalve unit and coupled to a movable valve member, the temperatureresponsive element configured to directly sense a temperature of asecond fluid by virtue of being in thermal contact via intermediatestructure or directly exposed to the second fluid and thereby actuatethe movable valve member from a first position to a second positionbased upon the temperature of the second fluid, the first positionconnecting a main inlet to a main outlet, the second position connectingthe main inlet to a heat exchanger outbound port and a heat exchangerinbound port to the main outlet; and a mounting base disposed at an endof the compressor valve unit for an external contact with a compressorpipe, the mounting base having a lateral periphery in thecircumferential and axial directions with dimensions sized to close offan accessory opening formed in an outer surface of the compressor pipe,the accessory opening oriented transverse to a bulk fluid flow path ofthe compressor pipe.
 10. The apparatus of claim 9, wherein the mountingbase includes a recess configured to receive a sealing member, whereinthe pipe to which the mounting base is configured to mount is annular innature, and wherein the mounting base forms a non-annular shape.
 11. Theapparatus of claim 9, wherein the mounting base is planar and includes agroove into which can be fitted a sealing member.
 12. The apparatus ofclaim 11, wherein the reconfigurable fluid flow paths are in fluidcommunication with the main inlet, the main outlet, the heat exchangeroutbound port, and the heat exchanger inbound port, and wherein thehousing includes a plurality of faces within which are located the maininlet, the main outlet, the heat exchanger outbound port, and the heatexchanger inbound port.
 13. The apparatus of claim 12, wherein thehousing is quadrilateral in cross sectional shape such that the maininlet, main outlet, heat exchanger outbound port, and heat exchangerinbound port are dispersed around the housing, and wherein thecompressor valve unit further includes a neck between the housing andthe mounting base.
 14. The apparatus of claim 12, which further includesa pipe having an internal passage structured to convey fluid betweenopposing openings on either end of the pipe, the pipe further includingthe accessory opening.
 15. The apparatus of claim 14, wherein the outersurface of the compressor pipe further includes an embossment to whichis attached the compressor valve unit.
 16. The apparatus of claim 15,wherein the embossment includes a planar mounting surface, wherein themounting base includes a planar base surface, and wherein the planarbase surface is configured to mount direct to the planar mountingsurface of the embossment.
 17. The apparatus of claim 16, which furtherincludes the compressor, an oil filter, and an oil heat exchanger.